Does an Intellect Devourer's host body provide additional experience?

[Rakshaka]

Simple question. Intellect devourers can ride in a number of devious and dangerous disguises. In some instances, the CR of the monster they have taken over can be higher than the IDs, though whether or not the host body is as combat effective depends on the nature of the host. Anyways, do you award XP for the host and the ID or just the ID?

[LazarX]

You award experience stricly for the Intellect devourer. It's ability to do things like this is part of it's CR.

[Rakshaka]

I thought so, but wanted second opinions. It is interesting that in some cases you have to recalculate the host's attacks due to the possible difference in BAB versus the IDs.
Thanks!